Luer activated devices (LAD) or valves (LAV) are commonly used in association with medical fluid containers and medical fluid flow systems that are connected to patients or other subjects undergoing diagnostic, therapeutic or other medical procedures. A LAD can be attached to or part of a fluid container or a medical fluid flow system to simplify the addition of fluids to or withdrawal of fluids from the fluid flow system.
Within the medical field there are a wide variety of medical fluid flow systems, serving a variety of functions. One of the more common uses of LADs are in association with fluid flow systems that are used for the intravenous administration of fluids, such as saline, antibiotics, or any number of other medically-related fluids, to a patient. These flow systems are commonly referred to as intravenous or “IV” fluid administration sets, and use plastic tubing to connect a phlebotomized subject to one or more medical fluid sources, such as intravenous solution or medicament containers.
Typically, such intravenous administration sets include one or more LADs providing needless access to the fluid flow path to allow fluid to be added to or withdrawn from the IV tubing. The absence of a needle for injecting or withdrawing fluid has the important advantage of reducing the incidence of needle stick injuries to medical personnel. A LAD typically includes a tapered female luer component, such as the inlet into a valve housing, that accepts and mates with a tapered male luer of a medical infusion or aspiration device, such as a needleless syringe or a administration set tubing brand.
There are certain characteristics and qualities of LADs that are highly desirable. For example, the LAD should provide a sufficient microbial barrier for the full service life of the valve. It is desirable that the microbial barrier be conducive to the application of standard aseptic techniques preformed by clinicians during the use of the device. For example, the geometry of the LAD should be such that it is easily swabbable and reduces the potential of entrapping particulates or contaminants that cannot be cleanly swabbed clear prior to use.
Furthermore, it is highly desirable that the LAD be substantially devoid of any interstitial space or any other “dead space” that cannot be flushed, or that such interstitial space be physically isolated from the fluid flow path. Such interstitial space has the potential of providing an environment for undesired microbial growth. In addition, the LAD should have a geometry that allows it to be sufficiently flushed so as to clear the dynamic fluid path and adjacent areas of residual blood or intravenous fluids to prevent undesired clotting.
LAD's are commonly used with intravenous catheters that provide access to a patient's vascular system. In such systems, another desirable feature of a LAD is minimal displacement of fluid during insertion and removal of the male luer. In certain situations, it is preferable that the LAD be a neutral/neutral device in that there is zero or only a very slight displacement of fluid during both insertion and removal of the male luer. In other situations it can be desirable for the LAD to produce a positive displacement of fluid from the valve housing during the removal of the male luer. The LAD also preferably prevents blood reflux into the catheter. Reflux is known to reduce the efficiency of the catheter and also to contribute to catheter clotting.
In most situations it is preferred that the LAD be ergonomically dimensioned to be completely activated by a wide range of ISO compliant male luer lock adaptors. However, there may be some instances when the LAD is specifically designed to be activated by a male luer connector that is not ISO complaint or may not be a luer lock male luer. Another desirable characteristic of a LAD is the ability of the LAD to seal against pressure contained within a fluid system to which the LAD is connected. For example, it is desirable to be leak resistance to positive pressures ranging from 10 to 45 psi and to negative pressures or vacuum from 1 to 5 psi. The LAD also preferably has a geometry that allows for easy priming and flushing that does not require any additional manipulations to remove residual air bubbles from the tubing system.
These and other desirable characteristics, which may be used separately or in combination, is preferably present over the full service life of the valve. When used in connection with an IV set or catheter, the LAD may go through many connections and disconnections. It is desirable that the life of an LAD last through upwards to about 100 connections and disconnections or 96 hours of dwell time.
As described more fully below, the fluid access devices of the present invention provides important advances in the safe and efficient administration or withdrawal of medical fluids to or from a fluid flow system.